rogers



(No Model.) v J. H. 81; J. W. ROGERS.

No. 326,675. Patented Sept. 22, 1885.

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ATENT F F ICE@ JAME HARRIS ROGERS AND J. EBB ROGERS, OF VASHINGTON, D.O.

MAeNETo-TELEPHONE.

SPECIFICATION forming part of Letters Patent No. 326,675, datedSeptember 22, 1885. Application filed December l), 1884. `(Nomodel.)

To all whom itmay concern,.-

Be it known that we, JAMES HARRIs Roe- ERs and J. VEBB ROGERS, citizensof the United States, residing at XVashington, District of Columbia,have invented certain new and useful Improvements in Magneto-Telephones,of which the following is a specification, reference being had to theaccompanying drawings.

Our invent-ion relates to magneto telephones; and it consistsin theconstruction and arrangement of the parts, which will be more fullyhereinafter described, and pointed out in the claims.

The object of our invention is to provide a compound magnet composed ofpiles of magnetized disks wherein the magnetism is concentrated at thecentral and peripheral portions thereof and carried within closeproximity to the diaphragm.

The several parts forming the compound magnet are magnetized separatelyby suitable mechanical means, and then mounted so as to form one magnetwith united parts, whose magnetic polar-ities are combined as one entiremagnet. The one polarity is concentrated and carried into closeproximity to the diaphragm by the magnet of the helix, while theopposite polarity is gathered from the peripheries and concentrated byan inclosing softiron ring and also carried upward to near thediaphragm. By this construction the combined effect of both theperipheries and centers of the several parts forming the entire magnetare caused to act conjointly, thus producing an instrument of strongmagnetic force, and at the same time more sensitive and efficacious thanhas heretofore been known or used, and one which is readily understoodand easily and cheaply manufactured. XVe attain these objects by thedevice illustrated in the accompanying drawings, wherein like letters ofreference indicate similar parts in the several views, and in which-Figure l represents a transverse vertical section of our improvedinstrument, with the ear-piece removed. Fig. 2 represents a modifiedform of the instrument, in that the core of the helix is movabletherein, being secured to a diaphragm of wood, mica, or like sub-Stance.

A represents an ordinary form of case, con` structed of suitablematerial.

B indicates an ordinary form of helix.

O is a soft-iron ring which surrounds the peripheries of the magnets andextends upward in close proximity to the diaphragm D, which, in theinstrument shown in Fig. l, is constructed of material ordinarily used.

E E represent the metallic disks composing the compound magnet, beingsecured by the screws c to the casing A.

In Fig. l the magnets E are illustrated as constructed of disks of metalconfined or secured by the screws e passing through the same. Theseplates or disks E are constructed of a suitable thickness and thenmagnetized separately. In magnetizfing the said disks they aresubjectedto the same process as the magnetization of any other form ofpermanent magnet, either by the use of a dynamomachine'or by abatterycurrent direct. It has been discovered that thc one pole of eachwill resolve itself at the center, and the other at the periphery of thesaid disks. Any suitable number of the disks are then formed into a pileand secured by suitable means.

In constructing the disks a hole, e', is bored in the center of eachone, and when they are secured together as a pile the said holes e allcombine to form a suitable opening for the reception of the core of thehelix B, which core extends through the pile of magnets at theircenters, and takes up the combined polarity at this point and carries itto Within close proximity to the diaphragm. The ring O encircles theperipheries of the said pile of disks E, touching the same, and carriesthe combined polarity at this point also to within a short distance ot'the diaphragm D.

In Fig. 2 the disks E are constructed of solid plates of metal withoutany hole or cavity formed in their central portion. In this instance thehelix B is constructed with an enlarged hollow central portion, in whichthe core B', which is secured at its one end to the diaphragm D, hasfree movement, the Whole acting on the principle of a solenoid. In thisinstrument the helix B may or may not be fastened to the magnetic pile.In this instance the soft-iron core will not rely wholly on the magneticaction ofthe pile or compound mag- IOO net for its magnetism, for, byits movement in the hollow helix, it is given thereby a sufficientstrength; but by the magnetic effect of the pile upon the said core itspolarity is increased, and the action of the diaphragm rendered vigorousand at the same time exceedingly sensitive.

The operation of the helix B is obvious, and as represented in Fig. 1the current, coming in to the helix from line, acts upon the diaAphragni by the Well-known inductive principle, the other end of the Wireof' the said helix beingvconnectcd up in the usual manner.

It is obvious that many minor changes could be made and substituted forthose shown and described Without in the least departing from the natureand principle of our invention.

Having thus described our invention, what We claiin as new, and desireto secure by Let ters Patent, isM

l. ln a magneto-telephone, the combination of a diaphragm, a pile ofmagnetized disks, a helix mounted in the center thereof. and asot'tironring encircling and touching the periphery of said pile, said helix andsoft-iron ring carrying the polarities of the parts With which theyengage Within close proximity to the diaphragm, and Vthe electricalconnections, substantially as described.

2. In a magneto-telephone, the combination of a diaphragm, a magneticpile, the hollow helix fastened to the said pile, the soft-iron coresecured to the diaphragm and having free movement in the hollow helix,the soft-iron ring encircling and touching the peripheries of said pileand extending Within close proximity to the diaphragm, and theelectrical connections, substantially as described.

3. VIn a magneto-telephone, the combination of the diaphragm D, casingA, magnetic disks E, forming a pile, a helix, B, engaging the centers ofsaid disks, a soft-iron ring, C, enciril'ng the peripherics of the disksand extending up within close proximity to the dia-Y phragm D, and theelectrical connections, substantially as described.

In testimony Wh'ereof We afi-lx our signa* tures in fpresence'of twoWitnesses.

JAS. HARRIS ROGERS. J. W. ROGERS.

Witnesses:

CHARLES S. HYER, EMMA M. GILLETT.

